Hearthstone: The Curse of Naxxramas is a fantastic idea for an expansion pack for the collectable card game - and one with interesting origins. You might imagine those lie in World of Warcraft, and you'd be half right: Naxxramas was a raid dungeon in that game, floating above Dragonblight in Northrend. (Or so it says on the internet. In common with a lot of Hearthstone players, I never really got into WOW - you don't need to know any lore in order to enjoy Hearthstone.) But if you ask me, the reason we have something like Naxxramas is more to do with Blizzard's core philosophy about what makes Hearthstone tick.
This was probably most evident in something lead designer Eric Dodds said at the start of the year. "Hearthstone is at its most fun when you're solving an interesting puzzle each turn," he explained. "Your opponent's minions, your minions and the cards in your hand are all pieces to this puzzle." This explanation caused consternation in some quarters - and it's true that there are deeper strategic and tactical layers to playing Hearthstone well - but I like it. No wonder Hearthstone has introduced so many people to collectable card games when it is this welcoming. Everyone loves a puzzle.
And now we have the single-player adventure of Naxxramas, which takes this approach to its logical conclusion: it turns Hearthstone into a pure puzzle game. Oh sure, it looks like you're just playing a card game against the AI, but really you're trying to figure out the solution to a specific puzzle Blizzard has set up for you. How do you overcome that weapon? That hero power? Those cards? Hearthstone is about creating a deck that is strong enough to overcome all sorts of opponents, but Naxxramas is about lateral thinking in the face of deliberate patterns.
Single-player content is a difficult area whether you're a card-battling game or a puzzle game, mind you, because whenever the going gets tough you will always have a slight suspicion the AI is cheating. Blizzard turns this on its head with typically impish flair: it cheats with relish. Rules that govern your deck construction and play are simply not respected on the other side of the board, where your AI opponents are given combinations of cards that you cannot have, hero powers that are outrageously overpowered and, in one case, even the ability to interrupt your turn halfway through. It reminds me of President Bartlet in TV's The West Wing, turning up to a basketball game with Rodney Grant as a ringer. When the cheating is so comically blatant, it just adds to the fun of beating the opponent.
And so it goes as you muscle your way past giant spiders, plague lords and corrupted paladins. Naxxramas is split into five 'wings' - the first is free - and each consists of three or four enemies, including a final boss. If you've played Hearthstone a decent amount, you will probably find it relatively easy on the default skill setting, which is more about introducing the various puzzle pieces you're going to have to cope with (new cards, new enemy hero powers) than putting up a particularly stern challenge. Victory in these bouts also gives you permanent access to some of the cards Naxxramas introduces (30 in total across all five wings), which you can then use in your general Hearthstone deck construction.
But things heat up when you go back for 'Heroic' encounters. You may have been able to get by with existing decks up to this point, but each Heroic fight will send you back to the construction screen to build something specific. How do you cope with Patchwerk, for instance, whose hero power destroys any minion he likes? You'll need plenty of minions on the board to mitigate the risk, or you'll have to rely on spells. And what about Faerlina, who fires off a missile for each card in your hand? You don't want to be holding a clutch of cards with nothing on the board or you're guaranteed to take a heavy whack to the face.
One of my favourite encounters is the Four Horsemen. Initially it seems like an easy fight: the enemy hero only has 15 health and there are three minions on the board, each with 15 health. The hero is impervious to damage while these three are alive, but surely you can deal with them. Except the Horsemen have all sorts of tricks in their saddle bags. There's a weapon that gains a huge damage bonus when the minions are dead - often enough to finish you off. And the hero uses a new secret that boosts the health and attack of a remaining minion when one of the others is dispatched, as well as an old secret that resurrects a fallen minion with a single health point, requiring yet more cards and turns to combat. It took an absorbing hour to figure out which class could get rid of those minions inexpensively and then resist that weapon.
That's Naxxramas at its best, then, but unfortunately it's not all like that, because there are also quite a few encounters that go beyond head-scratching intrigue. One obvious issue is that your puzzle solution usually relies on getting a very specific card (or cards) in your opening hand. If that doesn't happen, the whole thing can fall apart very quickly and you might as well concede and restart. But the bigger issue is just that many of these bosses feel like puzzles with only one solution, and once you've figured that out (or looked it up on the internet in frustration), it's just a question of getting the luck of the draw enough to succeed. In a sense, it all goes back to that core Hearthstone development philosophy, and perhaps Naxxramas actually betrays it: here it's the overall battle that is the puzzle, rather than the individual turn, and it doesn't seem to work quite as well.
Naxxramas has plenty of other things to recommend it, though, most notably those 30 new cards for use in all the regular online game modes. Nerubian Egg was the early star. It has no attack and only two health points, but on death it spits out a middleweight minion - four attack and four health. In other words, it's a minion that your opponent doesn't want to kill, disrupting their play, and if you're clever you can also figure out how to trigger it yourself. Echoing Ooze is another I like. "Battlecry: Summon an exact copy of this minion at the end of the turn." In other words, if you buff your ooze in that time, the copy will retain those effects, giving your opponent a bigger headache. Many of the new cards draw on the overall necropolis theme, too, employing the Deathrattle effect that activates when a minion is destroyed, something that hasn't been explored so thoroughly as things like Battlecry, so the collection is also nudging us in a new theorycrafting direction.
Most of the cards are neutral, meaning any class can make use of them, but Naxxramas also has class challenges, where you play against one of the AI enemies with a particular class and pre-ordained deck, often set up in a specific way. These fights are decent fun and completing them unlocks a new class-specific card. The Druid's Poison Seeds is a fun example: "Destroy all minions and summon 2/2 Treants to replace them." Maybe that transforms your weak minions into slightly better ones. Maybe it brings enemies down to size or helps you get around taunted minions. There are lots of possibilities.
There are some cards that feel a little dull or situational in the new batch of 30, but then the brief and intense history of Hearthstone itself is rife with stories of cards and classes that rose and fell in popularity at different times. Thanks to the popularity of Twitch streamers and deck-sharing sites, effective deck concepts get around like wildfire, leading to a lot of human opponents using identical decks, which then forces players hoping to innovate their way out of a rut to go off into the recesses of their card collections in search of new solutions. With 30 new cards in play, each one with unusual characteristics, it is a safe bet that this 'meta-game' will shift in favour of more and more of them as time passes, rather than just the dozen or so commonly in use at the moment. There will be specific combinations that only emerge in the future, either through experimentation and serendipity or because they suddenly counter a popular gambit.
Overall, The Curse of Naxxramas seems well worth owning, then. The solo content has its ups and downs, but it is most often fun, and also offers some welcome environmental refreshment. Things like a new game board, new music, new enemy emotes and all the trappings of Blizzard's typically lavish production values might sound trivial to some, but for those of us who have spent hundreds of hours playing Hearthstone already they are as much a part of the experience as anything else, and that shouldn't be overlooked. As for the new cards, the cunning behind many of them is likely to echo throughout the seasons, even though not all of them are showing up in regular play at the moment. And if you're anything like me, you won't want to be without them.
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